Question: Solve for $a$, $- \dfrac{a + 8}{4a + 1} = \dfrac{1}{3} $
Answer: Multiply both sides of the equation by $4a + 1$ $ -(a + 8) = \dfrac{4a + 1}{3} $ Multiply both sides of the equation by $3$ $ -3(a + 8) = 4a + 1 $ $-3a - 24 = 4a + 1$ $-24 = 7a + 1$ $-25 = 7a$ $7a = -25$ $a = -\dfrac{25}{7}$